1. Field of the Invention
The present invention relates to an optical transceiver module for an optical communication system, and more particularly, to a pluggable optical transceiver module which can be fit into or removed from a receptacle formed at the platform of an optical communication system.
2. Description of the Related Art
In optical communication, optical transceiver modules having both functions of transmitting and receiving an optical signal have been developed in various forms and have recently been standardized to a small and thin shape. In particular, a pluggable optical transceiver module is a standard suggested in the newest one among related multisource agreements (MSAs), which include a small form-factor pluggable (SFP)-MSA used for a transfer rate of 2.5 Gbps or less and a 10 gigabit small form-factor pluggable (XFP)-MSA used for a transfer rate of about 10 Gbps.
A pluggable optical transceiver module conforming to the SFP-MSA usually has a structure for receiving a duplex-LC connector used in a long-distance network. With the spread of an access network afterward, it is anticipated that the pluggable optical transceiver module has a form of a single optical fiber with a bi-directional optical transmission function.
An SFP optical transceiver module has an optical receptacle for fiber connector or a pigtailed fiber at one end and an electrical male connector at another end. The SFP optical transceiver module is mechanically and electrically coupled with an optical communication system through a electrical receptacle and a cage on the system board for preventing electromagnetic interface(EMI). Such pluggable method in which the optical transceiver module is coupled to the platform of the optical communication system is more convenient for test measurement and replacement than a method of fixing an optical transceiver module through soldering. In addition, pluggable electric connector is more advantageous in transmitting a high speed signal than a conventional pin-type connector.
The SFP MSA defines mechanical and electrical standards that should be complied with for an optical transceiver module, a cage assembly and an electrical connector, which are provided to fit the optical transceiver module to a platform of an optical communication system, so that compatibility can be accomplished regardless of manufactures and users. However, even if optical transceiver modules are the same SFP types, individual products may have different characteristics, merits, and demerits according to their manufacturers. In particular, since the SFP MSA was published on Sep. 14, 2000, various patents about a method of easily detaching an optical transceiver module from a cage assembly or a method of manufacturing and assembling a cage have been applied and registered.
Moreover, SFP optical transceiver modules may be connected using various types of connectors such as LC, SC, MT-RJ, BNC/TNC, and fiber channel or a fiber pigtail for interface with an outside. This allows that the SFP MSA is applied in various application fields. Also various types of optical transceiver modules and driving circuit boards may be combined internally. Accordingly, different SFP packages are manufactured and used according to the structure of parts included therein and the form of a connector.